This randomized, double-blind, single-center clinical trial was divided into two groups, RIMA-SVG and Ao-SVG, according to the surgical method. The purpose was to evaluate the effect of the RIMA-SVG surgical method in improving saphenous vein graft (SVG) patency and reducing clinical complications. A total of 300 patients will be enrolled and randomly assigned to two surgical method groups: RIMA-SVG Group (150 patients): SVGs are connected to the right internal mammary artery (RIMA). Ao-SVG Group (150 patients): The aorta is clamped, and SVGs are connected to the ascending aorta (Ao).All patients will undergo CABG on a beating heart with sequential vein grafts to bypass at least two or more coronary vessels. The primary outcome is 1-year graft patency. The secondary outcomes include neurological complications, mortality, major adverse cardiovascular events (MACE), and surgical site infection event.

This randomized, double-blind, single-center clinical trial was divided into two groups, RIMA-SVG and Ao-SVG, according to the surgical method. The purpose was to evaluate the effect of the RIMA-SVG surgical method in improving saphenous vein graft (SVG) patency and reducing clinical complications. A total of 300 patients undergoing CABG on a beating heart will be randomized into two surgical technique groups: RIMA-SV Group (150 patients): SVGs are anastomosed to the right internal mammary artery (RIMA). Ao-SVG Group (150 patients): The ascending aorta is clamped, and SVGs are anastomosed to the aorta. All patients will undergo CABG via median sternotomy, and the left internal mammary artery (LIMA) will be used to bypass the left anterior descending artery (LAD). SVGs will be sequentially grafted to the circumflex artery, diagonal branch, and right coronary artery. The primary outcome is 1-year graft patency, assessed by coronary CT angiography and classified using the FitzGibbon grading system. Secondary outcomes include all-cause mortality, major adverse cardiovascular events (MACE), neurological complications, and surgical site infection event. Patients will be followed at 12 months for clinical evaluations and imaging assessments. Inclusion criteria include patients aged 18 to 80 years undergoing planned CABG with at least two sequential saphenous vein grafts and who are able to provide written informed consent. Exclusion criteria include additional cardiac surgeries, severe subclavian artery stenosis, unsuitable SVGs (e.g. bilateral varicosities), history of intracranial hemorrhage, active bleeding, malignancy, or emergency surgery. Randomization will be computer-generated, and all aspects of the study will remain blinded to ensure unbiased assessments.

Inclusion Criteria:

1. Patients aged 18 to 80 years.
2. Scheduled for their first planned coronary artery bypass grafting (CABG) with at least two sequential saphenous vein grafts (SVGs).
3. Able and willing to provide written informed consent.

Exclusion Criteria:

1. Patients unable to provide written informed consent.
2. Patients requiring other cardiac surgeries (e.g. valve replacement, congenital heart defect surgery, or aortic dissection repair).
3. Patients with severe stenosis of the left or right subclavian artery.
4. Patients for whom aortic clamping is infeasible due to calcification of the ascending aorta.
5. Patients with bilateral SVG varicosities unsuitable for grafting.
6. Patients with active malignancy.
7. Patients with active bleeding or a history of bleeding tendency.
8. Patients with previous intracranial hemorrhage, ischemic stroke within 14 days preoperatively, or severe carotid artery stenosis.
9. Patients with severe hepatic dysfunction.
10. Patients requiring emergency surgery.

De-identified individual participant data (IPD) underlying the primary and secondary outcomes of the study-including baseline characteristics, graft patency results, perioperative complications, and 12-month clinical outcomes-will be made available upon reasonable request. Data will be shared with qualified researchers following study completion and publication, subject to approval by the trial steering committee and in accordance with ethical and data protection guidelines.

Data will be shared via request from the corresponding author starting 6 months after study completion and publication.

Access to the de-identified individual participant data will be granted to qualified researchers whose proposed use of the data has been reviewed and approved by the trial's principal investigator and data access committee. Applicants must submit a detailed research proposal outlining the scientific rationale, intended analyses, and data protection measures. A data use agreement must be signed prior to data release to ensure compliance with ethical and legal standards.

The surgical team is unblinded during the procedure, but patients and investigators remain blinded throughout the study.